Our 100 Night Sleep Trial includes a required 30-day Break-In period for your mattress. Sleeping on a mattress that has been built to your sleeping needs and preferences is usually a new experience, so your body will need time to get used to a new sleep system. Just like a new pair of shoes, the materials in the mattress need to be physically broken in. It may feel stiffer than you’d expect in the first few weeks but will adjust as you sleep on it.